Transactions are recorded automatically every 5 minutes from this page, which displays all Bitcoin transactions from Mt.Gox that have not been confirmed for 2 or more hours according to their wallet software.

Mt.Gox reports at least the following types of transactions through this API: withdrawals, dust sweeping, big output splitting. Some transactions have been spotted on this API recently with multiple successful block confirmations, which could just be a result of Mt.Gox wallet software not seeing the confirmations or could be new undocumented API behavior.